antichain in English dictionary antichain Meanings and definitions of "antichain" (mathematics) A subset of a partially ordered set such that any two elements in the subset are incomparable. noun (mathematics) A subset of a partially ordered set such that any two elements in the subset are incomparable. more Grammar and declension of antichain antichain ( plural antichains) antichain (plural antichains) more Sample sentences with "antichain" Declension Stem Try again Available translations Chinese Czech Finnish French Galician German Hungarian Italian Japanese Korean Polish Russian Slovak Spanish Ukrainian Vietnamese Authors